From £1M to £20M: What Actually Changes in Your Accounting

Here's a question I get asked a lot, usually in a quiet voice: "what actually changes when we get bigger?"

The founder asking is usually doing £2m or £3m, staring at £20m, and half-expecting me to say "nothing, it's all the same numbers, just bigger". It's not. The accounting that got you to £1m will not get you to £20m. The scary part is that most of the change doesn't creep up on you gradually. It arrives at specific thresholds, drawn in black and white by HMRC and Companies House. Cross the line and your life changes. Miss the line and it changes for you.

As a specialist social commerce accountant, I spend my days inside the books of UK brands doing between £1m and £20m. Let's walk the lines in order, and I'll tell you what actually changes, when, and what it costs if you're not ready.

The Reality Check: Twenty Times the Revenue Is Not Twenty Times the Work

It's worse than that. At a £40 average order value, £20m of revenue is 500,000 orders a year, roughly 1,370 a day. Every day you don't reconcile, that's 1,370 transactions of drift.

On £20m of standard-rated sales, roughly £3.3m of VAT flows through your bank account every year. It is not your money, and at this scale HMRC notices when it goes missing.

Corporation Tax Gets Real: Welcome to 25%

At £1m, you might still be playing with the small profits rate. Profit of £50,000 or less, you pay 19%. That's the rate your old accountant still quotes.

Profit over £250,000 and you're on the main rate: 25%. Between the two, marginal relief tapers you up. Most £10m brands are making £1m of profit or more, so they're firmly at 25%. On £2m of profit, which is a 10% net margin at £20m, that's £500,000 of corporation tax. A half a million pound bill. That's not a return you file in April. That's a number you plan around all year.

One more trap. If you've got multiple companies, the £50,000 and £250,000 thresholds are divided by the number of associated companies. Two companies, the thresholds halve. Founders who set up a new company for every venture often discover they've pushed themselves into the 25% rate at half the profit they expected. I have that conversation far too often.

You Start Paying Tax Before the Year Is Over

This one catches growing brands off guard. It's a cashflow event, not a tax event.

Once your annual profits go above £1.5m, HMRC classifies you as a large company. Large means you stop paying corporation tax nine months after year end and pay it in four quarterly instalments, two due before the year ends.

Run it with real numbers. £2m of profit, £500,000 of tax, four instalments of £125,000 each. The first one lands 6 months and 13 days into your accounting period. If your cashflow forecast doesn't have £125,000 sitting there in month seven, you're borrowing to pay HMRC, and HMRC doesn't pay interest on the favour.

The brands that handle this well treat corporation tax like a monthly standing order. The ones that don't, I meet in a panic, usually in month seven.

The Audit Arrives, Whether You Like It or Not

For financial years beginning on or after 6 April 2025, a private limited company is exempt from audit if it meets at least two of three tests: turnover no more than £15m, assets no more than £7.5m, 50 or fewer employees. At £20m, the exemption is gone. Turnover above £15m means audit, full stop.

And honestly, you'll want one by then anyway. Lenders, landlords, investors and marketplace partners all start asking for audited accounts. An audit isn't a punishment. It's a passport. The mistake is treating it as a surprise, not a scheduled event.

VAT Stops Being a Return and Becomes a Machine

At £1m, VAT is a quarterly chore. At £20m, it's a machine processing £3.3m a year through your bank account, and if it jams, everything downstream jams.

The questions change completely. Are you accounting for VAT on the sale price, not the payout? Are you separating marketplace-collected VAT from your own? Are your EU distance sales going through the OSS Union scheme so you're not registering for VAT in six countries one at a time? Are you reclaiming the VAT on your TikTok Shop fees, your FBA fees, your warehouse rent, your freight?

Making Tax Digital for VAT has been mandatory for you for years, so the returns are digital. The hard part is the reconciliation underneath: every settlement report tied back to the books, before the return is built, not after. If your finance team is still building VAT returns from a folder of export files at this scale, you're one mistake away from a very expensive conversation with HMRC. Our VAT registration checker and the TikTok Shop VAT checklist cover the traps at the smaller end. The principle is the same all the way up: reconciled books first, return second.

The Platform Data Problem Compounds

Here's what I tell founders heading this way. The platforms already report your income to HMRC under the digital platform reporting rules. TikTok, Amazon and Shopify all do it. The data matching is automatic.

At £1m, books that don't tie to the platform reports are a few thousand and an awkward conversation. At £20m, the difference is six figures and an enquiry that runs for a year. Same rules, completely different stakes.

This is why the systems from Scaling from £1M to £5M stop being optional. Weekly reconciliation, a chart of accounts by channel, stock valued properly, a monthly close you can defend. At £1m those are nice to have. At £20m they're the difference between knowing your numbers and guessing at them.

MTD for Income Tax Catches the Sole Traders

Sole traders and partnerships, this one's for you. Making Tax Digital for Income Tax is already here: over £50,000 of income, you were in from 6 April 2026. It tightens to £30,000 from April 2027, and down to £20,000 from April 2028. That last one catches nearly every serious seller left. Quarterly updates to HMRC from your software, not an annual scramble. If your accountant hasn't moved you onto compatible software yet, the clock is running.

The Structure Question: Where Does the Profit Live?

At £20m you're not one business anymore. You're a group wearing a trench coat, and groups have their own rules.

I'm not going to tell you to set up a holding company. It's not right for everyone, and anyone who tells you it is without seeing your numbers is selling something. What I will tell you is that the question gets real at this size: where profit sits, how you pay yourself, how you'd exit, and how the associated company rules hit your thresholds if you've already split into entities. Take these decisions with advice before you make them, not after HMRC has formed its own view.

And while we're on free points: the £10,500 Employment Allowance should be cutting your payroll bill from your first hire to your fiftieth. Most brands don't claim it properly.

What It Looks Like in One Table

Here's the journey, assuming a 10% net margin at each stage:

£1m revenue: £167,000 of VAT through the account a year. Corporation tax at 19% or marginal relief. No audit, no instalments.

£5m revenue: £833,000 of VAT through the account. Corporation tax at 25% if profit is over £250k. No audit or instalments yet, but both are on the horizon. Weekly reconciliation is non-negotiable.

£20m revenue: £3.3m of VAT through the account. Corporation tax at 25%, £500k on £2m of profit. Audit required above £15m turnover. Quarterly instalments if profit exceeds £1.5m, the first due before year end. Structure and transfer pricing start knocking.

My Contrarian Take: Don't Hire a CFO to Fix a Broken Ledger

At £8m or £10m, every founder's instinct is to hire a big finance name. Mine is the opposite. Fix the ledger first, hire the person second.

A CFO can't fix a system that records garbage. They'll spend their first year cleaning up a chart of accounts that should have been sorted in a week, and you'll pay six figures a year for the privilege. Hire the systems, then the person to run them. The order is the whole trick. That's the hill I'll die on, and I've watched brands prove it both ways.

Frequently Asked Questions

At what revenue do I need an audit?

A turnover test, not a profit test: above £15m of turnover, £7.5m of assets, or 50 employees, and you need two of three to stay exempt. At £20m, audit is mandatory. Budget for it.

When do I start paying corporation tax in instalments?

When annual profits go above £1.5m. Four quarterly instalments, two before your year end. A cashflow change as much as a tax change, so plan from around £1.2m of profit.

Do I need a holding company at this size?

Maybe, but not because a newsletter told you so. Get advice on your actual numbers. What's certain is that the associated company rules divide your tax thresholds, so structure decisions have real tax consequences.

When do I hire a financial controller or CFO?

When your month end takes more than two weeks, or when you're making decisions on numbers older than a month. Always after the systems are sorted, or they'll spend their first year cleaning.

Summary: The Lines Are Drawn, Know Where You Stand

Twenty times the revenue doesn't mean twenty times the work. It means new rules, drawn at specific lines: £250,000 of profit for 25% corporation tax, £1.5m of profit for quarterly instalments, £15m of turnover for audit, £20,000 of income for MTD, and platform reporting running underneath all of it.

None of these lines are a surprise. They're all published, knowable and planable. The brands that lose at this game aren't the ones who hit the lines. They're the ones who hit them sideways, without a plan, and paid for the privilege of being unprepared.

You've built the machine that sells. Build the one that counts, because at £20m, the counting is where the profit lives.

If you're doing £1m+ across TikTok Shop, Amazon or Shopify and you're not sure where your business sits against these lines, book a call. We'll map you against the thresholds in the first conversation. You can see how we've helped brands like yours on our case studies page, and if you're TikTok Shop heavy, we know your world: we live in the settlement reports.